[gtk+] Fix a crasher that was introduced by 9ca802161ec6387419d160f21fe477008a567477 due to preedit_str bei

[Cody Russell <bratsche src gnome org>]

commit 5ca0280cd3c663f4fb777890240b8fa27f45b837
Author: Cody Russell <cody jhu edu>
Date:   Thu Aug 15 15:08:34 2013 -0500

    Fix a crasher that was introduced by 9ca802161ec6387419d160f21fe477008a567477
    due to preedit_str being initialized as an empty string rather than NULL.

 modules/input/imquartz.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/modules/input/imquartz.c b/modules/input/imquartz.c
index 9e42d8f..06ebc68 100644
--- a/modules/input/imquartz.c
+++ b/modules/input/imquartz.c
@@ -230,7 +230,7 @@ discard_preedit (GtkIMContext *context)
   NSInputManager *currentInputManager = [NSInputManager currentInputManager];
   [currentInputManager markedTextAbandoned:nsview];
 
-  if (qc->preedit_str)
+  if (qc->preedit_str && strlen (qc->preedit_str) > 0)
     {
       g_signal_emit_by_name (context, "commit", qc->preedit_str);